1. Field of the Invention
The present invention generally relates to a rewritable optical information recording medium such as a CD-RW, a DVD-RAM, a DVD-RW, a DVD+RW and a PD, and more particularly to an optical information recording medium as typified by a phase change optical disk.
2. Description of the Related Art
Recently, high-speed recording and high-density recording of the optical information recording media have been in progress. Especially, optical disks using a rewritable phase change material for a recording layer have been widely used. As typical examples of such optical disks, there are CD-RW, DVD-RW, DVD+RW and the like.
These optical disks record unique and absolute address information called ATIP (Absolute Time in Pregroove) or ADIP (Address in Pregroove) thereon as a frequency-modulated signal by wobbling a groove provided on the optical disks. However, as faster and more high-density recording is achieved, reading the address information becomes difficult. Further, occurrence of address error increases due to deterioration of the groove and the recording layer caused by repeated recording. Thus, there is a problem in that after some number of repeated recordings the optical disk cannot be rewritten (overwritten) any more.
The address error is caused by the increase of jitter of an address signal. The jitter increases since a signal to be recorded has an influence on the address signal as noise. As far as the inventor of the present invention knows, there has been no prior art that considers a relationship between the degree of modulation and jitter of the address information on which frequency modulation is performed by wobbling the groove.